Machine tool transmission and control



ay 2, 193'! I J. a. ARMITAGE V zfifipzg MACHINE TOOL TRANSMISSION AND CONTROL Filed May 16, 1935 '7 Sheets-Sheet l f Q ATTORNEY J. B. ARMITAGE MACHINE TOOL TRANSMISSION-AND CONTROL 7 Sheets-3 2 .Filed May 1 35 RNEY 25, 137., J, ARMlTAGE 2&31388 MACHINE TOOL TRANSMISSION AND CONTROL Filed May 16, .1955 7 SheeC's-Sheet 5 25,. 19370 B ARMlTAGE Z,U81,288

' MACHINE TOOL TRANSMISSION AND CONTROL Filed May 16, 1955 '7 Sheets-Sheet 4 4. ATTORN EY y 1937. J. B. ARMITAGE 1 2,081,288

MACHINE TOOL TRANSMISSION AND CONTROL Filed May 16, 1955 7 Sheets-Sheet 5 M4 mo- IM l lNVENTOR MA? A I MQQNW y 1937- J. B. ARMITAGE 2,081,288

MACHINE TOOL TRANSMISSION AND CONTROL Filed May 16, 1935 '7 Sheets-Sheet 6 ATTORNEY May 25, 1937. J. B. ARMITAGE 2,031,283

MACHINE TOOL TRANSMISSION AND CONTROL Filed May 16, 1935 7 Sheets-Sheet 7 INVENTOR A Patented May 25, 1937 UNITED STATES MACHINE TOOL TRAN SMISSION PATENT OFFICE AND CONTROL Joseph B. Armitage, Wauwatosa, Wis., assignor to Kearney & Trecker Corporation, West Allis, Wis., a corporation of Wisconsin Application May 16, 1935, Serial No. 21,827

22 Claim.

use in milling machines, 'and especially for use 10 in planer or bridge types of milling machines.

Another object is to provide an improved transmission and control means for such machines in which certain tool and work actuating portions of the transmission are provided with 15 motor means individual thereto respectively, but

the control mechanism of the machine is so constructed and interrelated that the operation of one of the individual motors is restricted by the control devices of the other motor, and more 20 especially in a particular manner adapted for the operation of a milling machine.

Another object is to provide improved transmission and controls as mentioned in the preceding paragraph together with other means operative at times to overcome certain of the restrictions mentioned, whereby to then permit of control effects irrespective of the position or operation of certain of the restrictive control means.

A further purpose is to provide improved control means such as mentioned in the two last preceding paragraphs which are adapted for transmission mechanism in which the individual transmission motors are electrical.

A further purpose is to provide an improved milling machine transmission having separate and individual motors respectively for rotary tool movement and for relative movement of the work and tool together with improved control mechanism preventing such relative movement except work material.

A further purpose is to provide improved structure such as just mentioned in combination with- Another purpose is to provide an improved planer or bridge type of milling machine incorwhen the tool is rotating to effect cutting of the porating structure for some or all of the purposes previously mentioned.

Another purpose is to provide an improved multiple spindle milling'machine, in which the various spindles each co-operate with a single work support but are independently and individually adjustable either as to position, rate or direction.

Another purpose is to provide an improved multiple spindle milling machine such as just previously mentioned, in which the several spindles derive power from a common transmission member.

Another purpose is to provide 'an improved spindle rate changing and reversing mechanism, particularly adapted for use with the spindles of a multiple spindle milling machine for individual control of the rate and direction of the different spindles A further purpose is to simplify and improve the construction, operation and control of machine tools and especially of milling machines, and still other purposes, objects and results will be apparent from this specification.

The invention consists in the construction herein illustrated, described and claimed and in such modifications of the structure illustrated and described as may be equivalent to the structure defined in the claims.

The same reference characters have been used to indicate the same parts throughout the specification and in the drawings in which: I

Fig. 1 is a view in end elevation of a multiple spindle milling machine in which the invention is incorporated.

Fig. 2 is an enlarged partial view in front elevation of the same machine viewed from the left of Fig. 1, showing the mounting of certain control mechanism on the bed of the machine adjacent to the operators position.

Fig. 3 is a semi-diagrammatic reduced scale view of certain spindle units shown in Fig. 1 together with some of the spindle rotating and adjusting -mechanism therefor.

Fig. 4 is asectional'development of the table end of a transmission for driving the work table shown in Fig. 1.

Fig. 5 is a sectional development of other portions of the transmission for the table shown in Fig. 1. I

Fig. 6 is an enlarged partial top view, mainly in section, of the machine shown in Fig. 1 but 7 with the table removed.

. Fig. 7 is an enlarged sectional view of a portion of the mechanism shown at the right of Fig. 6, together with some associated mechanism.

Fig. 8 is an enlarged view in elevation, partly in section, of a spindle unit shown at the upper left in Fig. 1, here shown with the spindle in vertical position.

Fig. 9 is a partial view in horizontal section taken along line 9-9 of Fig. 8.

Fig. 10 is a partial view in vertical section taken along line Ill-J0 of Fig. 8.

Fig. 11 is a developed sectional view of a portion of the mechanism shown at the lower left of Fig. 8.

Fig. 12 is an enlarged top view of a spindle unit shown at the lower right of Fig. 1.

Fig. 1 3 is a partial view in vertical section taken approximately along-line I3I3 of Fig. 12.

Fig. 14 is an enlarged partial top view, mainly in section, of the upper portion of the structure shown in Fig. 1, the lower portions and spindle units being omitted.

Fig. 15 is a partial view in vertical section taken approximately on the line |5|5 of Fig. 2 and enlarged.

Fig. 16 is a partial view in vertical section taken approximately on the line IB-IG of Fig. 15.

Fig. 17 is a diagrammatic showing of certain control and transmission mechanism of the machine, and of certain interconnections thereof which exist in the machine.

The machine shown in the drawings is a milling machine of the so-called rail or planer type. The machine includes a work supporting table I, Fig. 1, guided by any suitable form of mutual guide surfaces for reciprocatory movement on a bed or base 2, between a pair of side column or support members 3, 4, which are rigidly fixed with the bed and are rigidly fixed together at their upper ends by a connecting frame member 5; the bed 2 and members 3, 4, 5 together constituting a unitary main frame or support.

Guided on side members 3, 4 for vertical adjustment is a rail or bridge 6. A plurality of spindle or tool support units 1, 8 are respectively guided on the side members 3, 4 for vertical adjustment. Other spindle or tool support units 9, III are each guided on rail 6 for horizontal adjustment and are simultaneously vertically adjustable bodily with the rail. The units 9, I0 each provide for angular or pivotal adjustment of the spindles carried thereby, and each of the spindles in each of the units 1, 8, 9, III is provided with means for axial adjustment, as will later be explained.

Supported by bed 2 at various points on the frame of the machine are a plurality of motors II, I2, I3 respectively providing primary moving means for the table I, for the several spindles of the units I, 8, 9, I0, and for the vertical movement of rail 6.

Table '1 is driven from motor I I, Figs. 1, 5, 6

which in this instance is electrical. Motor H is fixed with the main frame or support by a flange Ma. The transmission from motor II to table I is as follows:

The shaft of motor II is suitably coupled to drive a shaft I4, Figs. 5, 6 having fixed thereon a worm I5 meshing with a worm wheel I6 fixed on a shaft IT. A co-axial shaft I8 has fixed thereon a bevel gear I9 which meshes with a bevel gear 20 fixed on a shaft 2|,jthe shafts II, I8 being connected by an overload or safety coupling unit generally denoted by the numeral 22, which may be of any of a number of well known forms and therefore neednot be described in detail. The coupling 22 operates to cushion the transmission somewhat at all times and to interrupt the transmission during an overload, whereby to prevent damage or breakage but takes up its driving connection again when the load is reduced. The shaft 2| drives different branch line transmissions including a feed rate train and a relatively fast running rapid traverse train, either of which may alternatively actuate table I.

The feed rate branch of the table transmission includes a gear 23, Figs. 5, 7, fixed on shaft 2| which meshes with a gear 24 fixed on a shaft 25. Shaft 25 drives a shaft 26 through a rate changer generally denoted by the numeral 21 and which includes an intermediate shaft 28 and a plurality of reversible and interchangeably replaceable gear pairs such as the gear pair 29, 30 and the gear pair 3|, 32. shaft 26 drives a co-axial shaft 33 through a feed train safety coupling 34 substantially similar in operation and construction to the coupling 22. Shaft 33 has fixed therewith a worm 35, Fig. 4, which drives a worm wheel 36, Figs. 4, 7 supported for independent rotation on a shaft 31, and having fixed therewith clutch elements such as 38 which form terminal elements for the feed branch train.

The quick traverse rate branch of the table transmission includes a gear 39, Figs. 5, 7 fixed on shaft 2|, which meshes with a gear 40 fixed on a shaft 4|; A bevel gear 42, also fixed on shaft 4|, meshes with a bevel gear 43, Figs. 4, 7, which is supported for independent rotation on shaft 31, and is provided with clutch elements,

such as elements 44, which form terminal ele-' ments for the quick traverse branch train.

Alternatively actuable from the terminal clutch elements 38, 44, Fig. 4, is a clutch member 45, supported for axial shifting and independent rotation on shaft 31. Clutch member 45 has clutch teeth respectively at its opposite ends adapted to engage the different terminal elements of the feed and quick traverse trains. A gear 46 fixed with clutch member 45 drives a table reverser and interrupter generally denoted by the numeral 41, Fig. 4, through a gear 48 meshed with gear 46 and fixed with a reverser clutch member 49 which is supported for independent rotation on a shaft 50. Clutch member 49 is axially movable for alternative engagement of clutch teeth respectively at its opposite ends with complementary clutch elements respectively fixed with gears 5|, 52 which are each supported for independent rotation on shaft 50, andrespectively connected for opposite rotation of a sleeve 53, the drive from gear 5| being through a gear 54 meshed with gear 5| and fixed on sleeve 53, and the drive from gear 52 being through an intermediate gear 55 to a gear 56 fixed on sleeve 53. The clutch member 49 also has an intermediate disengaged position interrupting the drive to the sleeve 53. Slidably keyed with sleeve 53 is a table screw 51 which isrotatably supported but fixed against axial movement relative to the table I and which engages a nut 58 fixed in bed 2.

The table transmission mechanism described provides table movement selectively at any of a variety of feed rates, or alternatively at a quick traverse rate according to the position of clutch member 45, and in either direction according to the position of reverser clutch member 49, which may also be positioned to stop the table.

The table I may be manually adjusted, at times when the reverser clutch 49 is in central or neutral position, by a hand crank (not shown) a I I, 2,081,288 applied to the squared end 51a, Fig. 4, of table.

The spindle units 9, I9, Fig. 1, are similar to one another in construction except for the differences which arise from their right and left hand disposition on rail 6. Only the unit 9 will be described in detail.

Referring to Figs. 8, 9, 19, 11 the spindle unit 9 includes a saddle or member 59 guided for horizontal movement on rail 6 by any suitable slide surfaces, such for instance as shownin Fig. 19 and provided with suitable clamps operated by means such as bolts 69, 69. A block member 6| is pivoted on saddle 59, to swivel about the axis of a shaft 82, and may be clamped by bolts such as Ola, fitting a circular T slot in the saddle. The members 59 and GI together provide a unitary carrier for a cutter spindle or support member 93 which is carried by a quill'member 64 a bevel gear II which meshes with a bevel gear I2 fixed with a worm l3 engaging a rack I4 fixed with the quilL' The quill may also be clamped against axial movement by members such as I5, 15, Fig. 8, and clamp screws such as 16.

For swivelling the block member 6|, Fi 9, of the unit 9 there is provided a shaft 11, Figs. 8, 11, having an end I8 squared to receive a crank (not shown), and connected with a shaft 19' through bevel gears 89, 8|. Fixed on shaft 19 is a worm 82 meshed with a worm wheel segment 83 cut on or fixed with the block member iii.

The spindles of the spindle units 9 and I9, 1, are each driven through spindle transmission mechanism, which is similar for bothunits so far as it is individual to the different units, and except as it is relativelyreversed to-suit the right and left hand arrangement of the units, and is as follows for the unit 9. A drive shaft 84, Figs. 1, 8, etc., is rotatably supported from rail 6 and bodily vertically movable therewith, and provides a common drive shaft for the spindles of both the units 9 and I9. A bevel gear 85, Fig. 9, is rotatably carried by the saddle 59 and slidably keyed with shaft84 and drives the shaft 62 through a bevel gear 89 fixed thereon.

Shaft 82 drives an axially parallel shaft 81 through a pair of permanentlymeshedgears 88, 89. The shafts 82 and 81 are, therefore, driven in opposite directions of rotation. Either shaft may drive a shaft 99, Figs. 8, 10, which is equally distant from each shaft 62, 81, through a rate changer generally denoted by numeral 9i, Fig. 8, and consisting of removably reversible and interchangeable gear pairs such as the gear pair 92, 93, a plurality of such pairs being provided each having a different ratio of relative diameters. The rate changer 9| together with the shafts 62, 81, 99 constitutes a reverser, which drives shaft 99 in the one or the other direction accordingly as the driving gears of the rate change pairs 92, 93 are positioned on the one-or the other of drive shafts 62, 81. The ends of the reverser and rate changer shafts are exposed to receive the gear pairs underneath a hinged cover 9Ia,

I Fig. 9, which provides ready access thereto.

The shaft 99, Figs. 8, 10 drives spindle 83 of unit 9 through bevel gears 94, '95, a sleeve 96. a shaft 91 co-axial with the sleeve and slidabiy keyed therewith to form an extensible coupling, and a pinion 98 fixed on shaft 91 and engaging a gear 99 fixed on spindle 93, the shaft 91 and pinion 98 being journaled in a housing member I99 fixed on quill 54 to be adjustable-axially with the quill and spindle. Also fixed on shaft 91 is a fly wheel member IIII.

The spindle units I, 9, Fig. 1. aresimilar to one another in structure, except for the differences which arise from their respective right and left hand arrangement on the opposite side frame elements 3. 4. Only the unit 8 need therefore be described in detail.

Referring to Fig. 12, unit 8 includes a unitary carrier member I92 guided on the side member 4 by suitable mutual slide surfaces such. for instance, as shown. and clampable by suitable means operated by bolts such as the bolts I93. Carrier I92 rotatably supports a tool spindle or support I94, mounted for axial movement in a quill I95, the quill being movable by the means of a hand crank (not shown) applied to the squared end of a shaft I96, and clamped by bolts such as I91, the quill adjusting and clamping devices being identical in form and operation with those already described for the quill 95 of the spindle unit 9. Spindle I96 is driven from a vertical drive shaft I98, there being a. corresponding drive shaft I99, Fig. 1, associated with the side member 3 and corresponding unit I.

A spindle transmission connects the drive shaft I98, Fig. 12, for rotation of spindle I94, the transmission including gcaring, reverser and rate change means. extensible coupling means -etc.. substantially identical in all its elements'and functions with the spindle transmission connecting shaft 84 with the'spindle 63 of unit 9 as previously described. This transmission is shown, in part, in Fig. 13.

Each of the spindles of the units I, 81 '19 is driven from motor I2, Figs. 1, 3.6, which in'this instance is electrical and which has a flange I2a for fixing the motor to bed 2. The m'otor' shaft is suitably coupled to a-shaft IIO, which drives a cross shaft III through. a wormzandwormwheel H2, H3, the shaft III drivingthe vertical-shafts I98, I99 respectively through bevel gearrpairs H4, H5 and H6, H1. The shaft89 is driven from shaft III through bevel gears H8, H9, a vertical shaft I29, bevel gears I2I, I22, ashaft I23 and spur gears I24, I25. the shaft I29 being hidden from direct view in Fig. l by certain telescopic covers I29a; I

Each of the spindle units 1. 8 is manuallyverw tically adjustable by the means of a crank (not shown) applied to the squared ends of the shafts I29- or I21, Figs. 1, 3. Shaft I2! is connected for movement of unit 8 through bevel gears I28, I 29 and a screw I39 which engages a nut I3I, Fig. 12, fixed with the carrier I92. Shaft I26 is -connected with unit 1 through similar gear and screw means as shown in Fig. 3. Each of the units 9, I9 is manually horizontally movable on rail 6 by the means of a crank (not shown) applied to the squared ends of the cross screws I32, I 33, Figs. 1, 3, which are 3011! naled in rail 6. The screw I32 :engages a nut I34, Fig. 10, fixed with the carrier base 59 .of 9 and screw I33 engages a similar nut- .(not; shown) fixed with'the carrier'base of-unit-Ill;

Transmission mechanism is provided for vertical movement of the rail 6, Fig. 1, together with the spindle units 9, I0 carried thereby, as follows: The motor I3, Figs. 1, 14, which in this instance is electrical, is fixed on the frame member 5 by a flange I3a, and drives a shaft I35 suitably connected to the motor shaft. A shaft I36 is driven from shaft I35 through a worm I31 and wheel I38, as also is a co-axial shaft I39 which is angularly adjustable relative to shaft I36 by a coupling device I40 having adjustable T bolts I4I. Shafts I36, I39 respectively drive vertical screws I43, I44, Figs. 1, 14, through the bevel gear pairs I45, I46 and I41, I48, the screws I43, I44, respectively engaging nuts (not shown) fixed in opposite ends of the rail 6. The screws I43, I44 may be relatively adjusted for initially leveling the rail 6 by the means of the angular adjustment provided in the coupling I40.

The rail 8 is provided at each end with guide and clamp means cooperating with the side frame members 3, 4. The guide and clamp means may be of any suitable form but in this instance are similar at each end of the rail to the guide and clamp means shown in Fig. 12 for the spindle unit 8.

The table transmission reverser and inter ruptor clutch member 49, Fig. 4, may be manually shifted into either direction of engagement or out of engagement by a hand lever I49, Figs 1, 15 and may also be shifted out of either engagement by a table dog such as dog- I50, Fig. 15. The lever I49 is pivoted at I5I in a member I52 which is fixed on a shaft I53 upon which is also fixed a lever I54 having a pin portion I55 engaging a fork member I56 guided on a rod I51 and engaging the gear 48, Figs. 4, 15, between the arms of the fork member. The shaft I53 is also connected for rotation with a trip post I58 through a lever I59, Figs. 15, 16, and a rod member I60 which is pivoted with lever I59 at I6I, and at I62 is pivoted with a member I63 fixed on the trip post I58; The trip post I58 has fixed therewith an eccentric element I64 which, as the lever I49 is shifted to engage the reverser clutch member 49 in either direction, is swung into the path of movement of the dog I50, and the dog, upon subsequent movement of the table contacts the element I64 to return the clutch member to disengaged position.

When the dog I50, Fig. 15 has contacted and shifted the eccentric trip element I64, the table is stopped, and can not then be started again in the same direction by power so long as the element I64 remains in contact with the dog, such contact preventing movement of the lever I49 to re-engage the reverser clutch 49 in the same direction, although it can be engaged in reverse direction because such engagement moves the element I64 away from the dog. To permit immediate power movement of thetable in the same direction after dog tripping, the eccentric member I64 is arranged to be temporarily withdrawn from the path of the dog by the following means. Trip post I58 is normally held in the position of Fig. 15 by a spring I65 but may be moved axially to the left against the resistance of the spring by a movement of the lever I49 about the pivot I5I, the lower end of the lever contacting a slidable pin I66, which contacts at its other end with a pin or element I61 extended through a slot in shaft I53 and fixed on one end of a lever I68 pivoted at I69 and pperatively engaging the member I63 at its upper end. Release of the lever J49 returns the post I58 and trip element I64 to normal position to be contacted again by the table dog I50.

The table transmission feed and quick traverse clutch member 45, Fig. 4, may be manually shifted to drive table I at either feed or quick traverse rate by the means of a hand lever I10, Figs. 1, 15, which is fixed on a shaft "I having an eccentric pin member I12 fixed therewith and engaging a slot in a fork member I13, guided on a rod I14, and engaging the end faces of the gear 46.

Means are provided for preventing the previously described power re-engagement of table drive in the same direction after an automatic trip, at such times as the hand lever I10 is in the position effective for quick traverse. This consists of the interference elements I15, I16, respectively, swinging with the levers I49 and I10. When the lever I10 is in quick traverse position, the element I16 occupies a position of interference with the element I15 preventing pivotal movement of lever I49 about the pivot I6I. In the other, or feed position of lever I10 the lever I49 is not blocked.

Detent means are provided to define the several positions of the levers I49, I10, Fig. 15, and to yieldingly retain the levers in the positions to which they are shifted. I For the lever I49 the detent means includes a cam member I11, Fig. 16, fixed with the member I54 and which cooperates with a pivoted element I18, the elements being urged together by a spring I19. For the lever I10 the detent means includes a cam member I60, Fig. 16, fixed with the right hand end, Fig. 15 of shaft HI, and cooperating with a pivoted member I8I urged by a spring I8Ia.

In addition to the interconnection of controls preventing operation of the table at quick traverse rate at certain times, as previously described, there are provided certain other inter-relations and interconnections of transmission and control mechanism. Certain of this control mechanism can be used in a variety of forms or will take various forms depending upon the nature of the power supply, as for instance whether the power supply source is mechanical, hydraulic or electrical, and depending upon the type of current available for the electric motors such as here shown. For these reasons the drawings, Fig. 1'1, relating to the interconnection of controls, are diagrammatic.

In the diagram, Fig. 17, the motors 11, 12 used for purposes of illustrating the invention, are electrical in nature and of a type requiring a three wire current supply line comprising the line wires I82, I83, I64. Also in Fig. 17 the other portions of the table and spindle transmissions previously described are diagrammatically represented by a limited number of their ele ments. Thus the transmission from motor II to table I shows the feed rate changer 21 and the feed rate terminal clutch element 36, the quick traverse rate terminal element 44, the rate selective clutch member 45, the reverser 41 and the two safety devices 22, 34, all connected in the relative train positions previously explained, together with the feed and quick traverse selective lever I10 and the reverser control lever I49 which are shown connected to the parts controlled thereby by dotted lines.

Also in Fig. 17 the connection of the spindle motor I2 to a representative spindle, which might be the spindle 63 of the spindle unit 9, or any of the spindles of the various spindle units 1, 8, 9, I0, is shown, including the reverser and rate changer 9| of Fig. 8.

The motor I2, Fig. 17, is supplied with line our-- 1 rent through a control switch generally denoted by the numeral I85 including three live contacts I88, I81, I88 and three movable contacts such as I89,

' I90, I9I, which are connected for simultaneous movement in a direction to open the switch I85 by a spring I92, and for opposite movement, to close switch I85, by a solenoid I93. Current to actuate solenoid I93 is derived from the line in the first instance, to start motor I2, through a switch generally denoted by the numeral I94, which is normally held open by a spring I95 but may be closed by a manually movable member I90, whereby the solenoid I93 is energized, and the switch I85 is closed and motor I2 starts spindle rotation. When the solenoid I93 is energized it closes an auxiliary switch thereby completing a holding circuit which provides another path for current to energize solenoid I93, and the switch I94 may then be released by the operator without de-energizing the solenoid. Motor I2 therefore continues to run, but the solenoid can be later de-energized to stop the motor at any time by opening a switch I91 in the holding circuit by the means of a manually movable member I98, this switch being normally held closed by a spring I99.

An overload safety device generally denoted by the numeral 200, is provided for motor I2, as follows, current to the motor passes through heating elements 20 I, 202, with which is associated a thermostaticelement 203 which, when heated beyond a certain temperature, operates a switch 204 to an open position. The switch 204 is in the supply line of the solenoid I93, and when the switch is opened the solenoid is de-energized. This opens switch I85 to stop the motor I2 .and the motor cannot be started again 'except by manual operation of switch I94 as previously described.-

Similarly operative control means are provided for the table motor II, consisting of a main motor supply switch 205, Fig. 17, which is opened by a spring 206 and closed by a solenoid 201, the solehold-being initially energized to start the motor by closing a normally open switch 208, operative to closed position by a manually movable member 209. Following this the solenoid is energized, during motor operation, through a solenoid operated switch 2 I0, and may be later de-energized to stop the motor by opening a normally closed switch 2I I, by the means of a manually operable member 2I2. The solenoid 201 for motor II is also energized through an overload safety device 2 I3 similar to the device 200.

devices of the spindle transmission through motor I2. Thus the table I, except as later pointed out, cannot be actuated from motor II except when the motor I2 is running. Also, if the spindle transmission is stopped, either by the switch I91 or the overload device 200 the table transmission is likewise stopped, and if thus stopped, a subsequent starting of the spindle transmission will simultaneouslystart the table transmission. At

the same time the table transmission is subject to all of the control devices previously mentioned including the mechanical control levers I49, I10, the

overload devices 22, 34 and the rate changer 21, as

well as the switches 208, 2II and the overload device 2I3.

One reason for the described interconnection of table and spindle control devices is to prevent operation of the table at a feed rate when the spindle transmission is not running. The feed rate may be relatively very slow in some of the adjustments of rate changer 21, and the operator might then, unless prevented inadvertently leave the transmission engaged to feed a work piece against a non-rotating cutter, thereby damaging or breaking the machine.

' Such considerations for various reasons do not affect the use of table rapid traverse rate when the spindle is not rotating. In this case the table rate is invariably so rapid that the operator will not inadvertently leave it engaged. It is very desirable for various reasons that table rapid traverse should be available whether the spindles are or are not rotating. To effect that result the controls'for motor II- are interconnected with the lever I10, Fig. 17 in such manner that the solenoid 201 is energized to close motor switch 205 at all position, as follows:

A switch generally denoted by the numeral 2 I4, Fig. 17, includes a contact 2I Ia connected to the main line conductor I84 in manner to exclude the spindle motor control mechanism and a contact 2I5 connected to thesolenoid 201 in manner to exclude each of the several table motor control switches 208, 2 I0, 2| I, but to include the overload device 2I3. A bridging element 2I6 is connected. for movement from'lever I10, the element being fixed on a pivoted lever 2 having an end 2I8 operative from a rod or bar M9 through a lost motion connection including the spaced apart contact pins 220, 22I fixed on rod 2I9, the rod being pivoted with the lever I10 at 222. A spring 223 operates to urge the lever end 2I8 against the one or the other pin 220, 22I during the first portion of movement of lever I10 in either direction, but at about the intermediate point of lever movement the spring crosses the center of the pivot of lever 2I1 and then uickly completes the movement of the bridge element 2 I 0.

The arrangement just described is such that,

' asthe lever I10 is moved from feed to quick traverse position the bridge member 2I0 completes the circuit to solenoid 201 through switch 2I3 after the clutch member 45 disengages from feed terminal element 38, and before the clutch member 45 is fully engaged with the quick traverse terminal member 44-. In the opposite lever movement, the circuit through switch 2M is maintained closed during the first part of the movement of lever I10 toward feed position, but is opened again before the clutch member 45 reaches a position to engage the feed terminal element 38.

As a result of the action just described the table transmission motor I I may run duringquick traverse position of lever I10, irrespective of the controls previously described, excepting only the control 'from the overload device 2I3, but without altering the efiect of the interconnection of control means which prevents the operation of the table I at feed rate when the spindle motor I2 is not running. 7

The primarily manually operable elements of the control mechanism described are arranged at the operators position and in a form for convenient manipulation. Referring to Fig. 2, the levers I49 and'I10 are mounted on base 2 at a point adapted for manipulation by the operator when in best position for observation of the work and tools. Closely adjacent to the right hand of the operator is a control panel generally denoted by the numeral 224, upon which are mounted the manually operable switch elements I96, I98, 299, 2I2.

Other control elements, such as switch operating elements 225, 226 for a pump motor (not shown) and the switch operating elements 221, 228 for the rail operating motor I3 are also mounted on panel 224. The elements 221., 228 operate a main switch and control solenoid (not shown) for motor I3 which are similar to the switch I85 and solenoid I93 for motor I2, and which are similarly controlled from switches, (not shown) corresponding to the switches I9, and I91.

I claim:

1. In a machine tool including a bed and a plurality of elements each movably supported on said bed, the combination of a transmission for movement of one of said elements including a power operable motor constituting a primary motion source, a transmission for movement of the other of said elements including a second power operable motor constituting a second primary motion source, control means including a main power switch operative for alternative connection and interruption of power to the first mentioned motor, other control means individually operable for alternative connection and interruption of power to said second motor, and relay switch means deriving power through said main power switch and operative for interrupting the power connection to said second motor when the power connection to the other motor is inoperative.

2. In a milling machine having a main supporting structure and a reeiprocatory work support carried thereby; the combination with a tool spindle supporting unit including a base guided for bodily movement on said main supporting structure, a member supported on said base for pivotal movement relative thereto, and a tool spindle rotatably carried by said pivoted member and bodily movable therewith in cooperating relation? ship with said work support; of mechanism for rotating said spindle including a source of power carried by said main supporting structure, constant speed transmission mechanism disposed to transmit power at a substantially constant relatively high speed from said source to said pivoted member, and a rate changer carried by said pivoted member for-bodily movement therewith and operative to transmit power from said constant speed mechanism to said spindle at a selected one of a. plurality of rates, whereby said spindle may be operated at low speed and high torque without subjecting said constant speed transmission mechanism to high torque thereby avoiding deflection of said mechanism and vibration of said spindle.

3. In a milling machine having a bed, a work supporting table reciprocably mounted on said bed, and a pair of spindle supporting members fixed with said bed and uprising respectively at opposite sides of said table; the combination with a rail guided on said uprising members above said table and arranged for vertical movement relative thereto, a tool spindle supporting unit including a base slidably mounted on said rail for bodily movement relative thereto, and a tool spindle rotatably carried by said base for bodily movement therewith in cooperative relationship with said work table; of mechanism for driving said spindle including a power source carried by said bed, a transmission mechanism disposed to transmit power from said source to said movable base at a substantially constant relatively high speed. and a rate changer carried by said base in man: ner to move bodily therewith and operative to transmit power from said constant speed mechanism to said spindle at a selected one of a plurality of rates, whereby vibration of said spindle is obviated by avoiding transmission of power to said base at low speed and high torque,

4. In a milling machine having a main supporting structure and a reciprocatory work support carried thereby, the combination of a spindle unit including a base guided for bodily movement on said structure in a direction transverse to the path of table movement, a pivoted member carried by said base for movement on an axis substantially parallel with the path of movement of said table, another member carried by said pivoted member for movement in a path transverse to table movement, a tool spindle rotatably journaled in the last mentioned member, and a transmission for rotation of said spindle including a driving source carried by said supporting structure, a shaft driven from said source and axially coincident with the axis of said pivot and a rate changer carried by said pivoted member and driven from said shaft.

5. In a milling machine the combination of a main support structure including a bed, a table guided on said bed for horizontal reciprocatory movement, said main support including a plurality of spindle support members uprising respectively at opposite sides of said table, a rail guided on said members for vertical movement transverse to table movement, a spindle unit ineluding a base guided on said rail for horizontal movement transverse to table movement, a member pivoted on said base for movement about an axis substantially parallel to table movement, a spindle carried by said member for rotation on an axis transverse to table movement, and a transmission for rotation of said spindle including a power shaft axially coincident with said pivot axis and a rate changer carried by said pivoted member and driven through said shaft.

6. In a milling machine. the combination of a main support structure including a bed, a table guided on said bed for horizontal reciprocatory movement, said main support including a plurality of spindle support members uprising respectively at opposite sides of said table, a rail guided on said members for vertical movement transverse to table movement, a spindle unit including a base guided on said rail for horizontal movement transverse to table movement, a member pivoted on said base for movement about an axis substantially parallel to table movement, another member guided by said pivoted member for movement transverse to table movement, a spindle carried by the last mentioned member for rotation on an axis transverse to table movement, and a transmission for rotation of said spindle including a power shaft axially coincident with the axis of said pivoted member. and a spindle rate changer driven from said shaft and carried by said pivoted member.

'7. In a milling machine the combination of a supporting structure including a bed, a work table guided on said bed for reciprocatory movement, a plurality of spindle units each including a base member guided for bodily movement on said structure in a direction transverse to the path of mechanism for rotation of said spindles including for each spindle a rate changer carriedby the unit base associated therewith, and bodily movable with said base and spindle and adjustable to effect rotation of said spindle at any one of a plurality of rates.

8. In a milling machine, the combination of a supporting structure including a bed, a work table guided on said bed for reciprocatory movement. a plurality of spindle units eachincludlng a base member guided on said structure for bodily movement in a path transverse to the path of table movement and each including a tool spindle carried by said base member for rotation on an axis transverse to the path of table movement, transmission mechanism for'said reciprocatory table movement including a rate changer and reversing means, and transmission mechanism for rotation of said spindles including first and second reversing means respectively individual to the different spindle units and respectivelycarried by the different of said base members for bodily movement therewith.

9. In a milling machine the combination of a supporting structure including a bed, a work table guided on said bed for reciprocatory movement, a plurality of spindle units each including a. base member guided on said structure for bodily movement in a path transverse to the path of table movement and each including a-tool spindle carried by said base member for rotation on an axis transverse to the path of tablemovement, transmission mechanism for said reciprocatory table movement including rate change and reversing means, and transmission mechanism for rotation of said spindles including for each spindle rate change and'reversing means individual thereto and carried by the base member associated therewith for unitary bodily movement with the base member and spindle.

sitely rotatable shafts and a driven shaft each carried by said base in axially parallel spaced arrangement, and gearing interchangeably mountable on said shafts to drive said driven shaft from the one or the other of said oppositely rotatable shafts, whereby to actuate said spindle in either direction of rotation.

11. In a milling machine the combination of a supporting structure including a bed, a table 'reciprocably guided on said bed, said structure including a plurality of spindle support members uprising from said bed on opposite sides of said table respectively, a plurality of tool spindles each rotatably supported from said structure at a level above said table and axially transverse to the path of table movement, a plurality of independently power operable motors each supported from said structure, a table transmisison driven from one of said motors, a plurality of spindle transmissions respectively for diflerent oi said spindles and each driven from the other of said motors;

and control devices for said transmissions including a spindle transmission controller and a table transmission controller respectively for alternative connection or disconnection of power to said a table and to said spindles, said controllers being independently operable, means interconnecting said control devices to render the table transmission controller inoperative for said power connection when the spindle transmission controller is in power interrupting position, other independently operable control means operable to alter the motion transmitting connection of said table transmission, and means operative from the last mentioned control means and operable to establish power connection to said table irrespective of the position of said spindle transmission controller.

12. In a milling machine the combination of a supporting structure including a bed, a table reciprocably guided on said bed, said structure including a plurality of spindle support members uprising from said bed on opposite sides of said table respectively, a plurality of tool spindles each rotatably supported from said structure at a level above said table and axially transverse to the path of table movement, a plurality of independently power operable motors each supported from said structure, a table transmission including a feed rate branch line, a quick traverse rate branch line and means selectively shiftable'to connect the one or the other of said branch lines to actuate said table, said feed rate branch line including a feed rate changer, and saidbranch lines being alternatively connectible to actuate said table from one of said motors, a plurality of,

other branch lines respectively individual to different of said spindles and each connected for operation from the other of said motors; and control devices for said transmissions including a spindle transmission controller and a table transmission controller respectively for alternative connection or disconnection of power to said table and to said spindles, said controllers being independently operable, interconnecting means effective to render said table transmission controller inoperative for Said power connection when the spindle transmission controller is of power interrupting effect, a third independently operable controller shiitable for said alternative connection of feed rate and quick traverse rate branch lines, and means operative only in the quick traverse connecting position of said third controller to establish power connection to drive said table irrespective of the effect of said interconnecting means.

13. In a milling machine the combination of a base, a tool spindle rotatably supported from said base, a work table supported from said base for reciprocatory movement in a direction transverse to the spindle axis, a plurality of power operable motors each supported from said base, a spindle transmission connectible from one of said motors for rotation of said spindle and including a spindle rate changer, a table trans-- mission including a feed rate branch line and a quick traverse rate branch line and means shiftable for alternative connection of said branch lines to actuate said table, said feed rate branch line including a feed rate changer and each of said branch lines being connected for actuation from the other of said motors; and control devices for said transmissions including a spindle transmission controller and a table transmission controller respectively for alternative connection or disconnection of power to operate said spindle and to operate said table, said controllers being independently operable, means adapted to render said table transmission controller inoperative for power connection when said spindle transmission controller is in power interrupting posi tion, a third independently operable controller for operation of said shiftable means to alternative feed or quick traverse rate connection, and means operative only in the quick traverse rate position of said third controller to establish a power connection to drive said table.

14. In a milling machine the combination of a base, a tool spindle rotatably supported from said base, a work table supported from said base-for reciprocatory movement in a direction transverse to the spindle axis, a plurality of power operable motors each supported from said base, a spindle transmission connectible from one of said motors for rotation of said spindle and including a spindle rate changer, a table transmission including a feed rate branch line and a quick traverse rate branch line and means shiftable for alternative connection of said branch lines to actuate said table, said feed rate branch line including a feed rate changer and each of said branch lines being connected for actuation from the other of said motors; and control devices ior said motors including a plurality of independently operable controllers respectively for alternative connection or disconnection of power to operate the different motors, another independently operable controller for shifting said shiftable means to alternative feed or quick traverse position, and means operative from said other controller to effect a power connection to Said table motor transmission whenever said other controller is in quick traverse rate position.

15. In a milling machine the combination of a base, a tool spindle rotatably supported from said base, a work table supported from said base for reciprocatory movement in a direction transverse to the spindle axis, a plurality of power operable motors each supported from said base, a' spindle transmission connectible from one of said motors for rotation of said spindle and including a spindle rate changer, a table transmission including a feed rate branch line and a quick traverse rate branch line and means shiftable for alternative connection of said branch lines to actuate said table, said feed rate branch line including a feed rate changer and each of said branch lines being connected for actuation groin the other of said motors; and control devices for said transmissions including a plurality of independently operable controllers respectively for alternative connection or disconnection of power to said table and to said spindle, another independently operable controller for shifting said shiftable means to alternative feed or quick traverse position, and means operative to control the power connection to operate said table in accordance with the position of said other controller.

16. In a machine tool including a bed and a plurality of elements each movably supported on said bed, the combination of a transmission for movement of one of said elements including a power operable motor constituting a primary motion source, a transmission for movement of the other of said elements including a second power operable motor constituting a second primary motion source, control means operative for alternative connection and interruption or power to the first mentioned motor, other control means individually operable for alternative connection and interruption or power to said second motor. means interrupting the power connection to a predetermined one of said motors when the power connection to the other motor is interrupted, and another independently operable control means operative to effect a power connection to said predetermined motor irrespective of said interrupting means.

17. In a machine tool the combination of a rotatable spindle, a support, said spindle and support being relatively bodily movable, a transmission ior rotation of said spindle including a first power operable primary motion source, a transmission for said bodily movement including a second power operable primary motion source: and control means for said transmissions including a plurality of independently operable converse to the spindle axis, a plurality of power operable motors each supported from said base, a spindle transmission connectible from one of said motors for rotation of said spindle and including a, spindle rate changer, a table transmission including a feed rate branch line and a quick traverse rate branch line and means shittable for alternative connection of said branch lines to actuate said table, said feed rate branch line including a feed rate changer and each of said branch lines being connected for actuation from the other of said motors; and control devices for said motors including a spindle transmissionmotor controller and a table transmission motor controller respectively for alternative connection or disconnection of power to operate the spindle and table motors, said controllers being independently operable, means adapted to render said table transmission motor controller inoperative for power connection when said spindie transmission motor controller is in power interrupting position, a third independently operable controller for operation of said shiitable means to alternative feed or quick traverse position, and means operative only in the quick traverse position of said third controller to estab- 11511 a power connection to drive said table transmission motor irrespective of said interrupting means.

19. In a milling machine the combination of a base, a tool spindle rotatably supported from said base, a work table supported from said base for reciprocatory movement in a path transverse to the spindle axis, a plurality of electric motors each supported from said base. a spindle transmission connectible from one of said motors and including a spindle rate changer, a-tabie transmission including a feed rate branch line and a quick traverse rate branch line and means shiftable for alternative connection of said branch lines to drive said table. said feed rate branch line including a feed rate changer, and each of Ill control means for the table transmission motor switch means including means operative to deenergize said table transmission motor when the spindle motor switch means is open and the shiftable means is concurrently in position to connect said feed rate branch line.

20. A milling machine as specified in claim 19 including other controlmeans operative in accordance with the operation of said first controller to close the table transmission motor switch means when said first controller is in quick traverse position.

21. In a milling machine the combination of a reciprocatory table, a rotatable tool spindle, a spindle transmission including an electric motor means, a table transmission including means operable for actuation of said table alternatively at a quick traverse rate or at arelatively slow feed rate and including other electric motor means, an electric power line, switch means for alternatively connecting or disconnecting each of said motor means with said power line, means preventing connection of said table to be actuated at said feed rate when said power line is disconnected irom said spindle motor means, and other control means for connecting said other motor means to actuate said table at a quick traverse rate irrespective of the connection of said spindle motor means.

22 In a machine tool having a rotatable tool spindle and a work support mounted in cooperating relation therewith for movement relative thereto, the combination with a motor operatively connected to drive said spindle, another motor for driving said work'support, and a transmission mechanism operatively connecting said work support motor to said work support, said mechanism being adjustable in manner to move said work support selectively at either feed rate or rapid traverse rate; of control mechanism' for said motors including means operative to stop said work support motor upon stopping of said spindle motor when said transmission mechanism is adjusted to operate at feed rate, and means operative to 'eflect energization of said work support motor independently of said spindle motor when said transmission mechanism is adjusted to effect operation of said work support at rapid traverse rate.

' JOSEPH B. 'ARMI'I'AGE. 

